Spiny rush is a clumping plant 1–2 m tall that has very sharp tips on the leaves and stems. It can outcompete native plants and injure people and animals.
Spiny rush is a serious threat to coastal saltmarsh, which is an endangered ecological community in NSW.
Sharp rush is a clumping perennial plant that grows in a dome shape. Usually it is 1- 1.2 m tall but occasionally can reach 2 m.
The flowering stems and leaves look very similar. The stems are 30-160 cm long and 2-4 mm in diameter and the flowers forms below the tip. The leaves are slightly smaller and have a yellow to golden brown sheath. Both stems and leaves are:
Spiny rush also produces short creeping underground stems called rhizomes.
Spiny rush looks similar to many other Juncus species. In NSW there are 43 native juncus and 20 naturalised introduced species. Spiny rush's key feature is the very sharp pointed leaves and stems.
The native Sea rush Juncus kraussii looks very similar but it only grows in coastal areas. Its stems and leaves are also sharp but not as sharp or as stiff as spiny rush. Native sea rush is more upright and vertical than the dome-shaped spiny rush. The capsule is smaller only up to 3 mm long. The seeds are also smaller (0.5-1.0 mm) and they do not have papery tails at each end.
There are scattered infestation in many regions of NSW. The main infestations are in the Greater Sydney, Hunter, Murray and South East regions.
This plant is native to Southern Europe, the Mediterranean region and Western Asia.
Spiny rush grows in temperate climates. It tolerates soils with low fertility and saline soils. Plants can grow in shallow salty water. In NSW it has been found growing in:
Plants do not flower until they are two years old. Mature plants can produce up to 4000 seeds per year and the seeds can remain viable after many years in the soil. Seeds are spread mainly by water. They are also moved by:
Plants can grow from pieces of the crown or rhizomes. These can be spread by cultivation, earth-moving equipment and when contaminated soil is moved to a new area.
Brown, K., & Bettink, K. (2006). Biology of Sharp Rush,* Juncus acutus. In Managing Sharp Rush (* Juncus acutus), Proceedings of a workshop held at Wollaston College Conference Centre, Mt Claremont Perth, Western Australia. WA Department of Environment and Conservation.
Daly, T. (2013), Coastal saltmarsh. Primefact 1256, NSW DPI.
Identic Pty Ltd. and Lucid central (2016). Environmental Weeds of Australia Fact sheet: Juncus acutus Retrieved: 8 February 2023 from: https://keyserver.lucidcentral.org/weeds/data/media/Html/juncus_acutus_subsp._acutus.htm
Parsons, W.T., & Cuthbertson, E. G. (2001). Noxious weeds of Australia. CSIRO publishing.
PlantNET (The NSW Plant Information Network System). Royal Botanic Gardens and Domain Trust, Sydney. Retrieved 8 February 2023 from: https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Juncus~acutus
Sainty, G. R., & Jacobs, S. W. (2003). Waterplants in Australia (No. Ed. 4). Sainty and Associates Pty Ltd.
Wear personal protective clothing to prevent injuries from the sharp stems and leaves when controlling this plant.
Dense infestations can be removed using cutters, graders or ploughs. Cultivation can also be effective but plants need to be collected and disposed of. Burning is an effective disposal method. Resow pastures or revegetate treated areas. Use salt tolerant species in saline areas.
Wiping can be used on spiny rush growing in crops or pastures. The wiper needs to be at least 10 cm higher than the crop or pasture and the spiny rush must be at least 15 cm higher than the crop or pasture. If plants have many dead leaves or stems it is best to slash first and then wipe when the spiny rush regrows to a suitable height.
See Using herbicides for more information.
Glyphosate 360 g/L
Rate: 1 L of herbicide in 2 L of water
Comments: Apply by wiper application to actively growing plants. Wiper application should be a minimum of 10 cm above the crop or pasture and weeds should be at least 15 cm above the crop or pasture, See label for more instructions.
Withholding period: Nil.
Herbicide group: 9 (previously group M), Inhibition of 5-enolpyruvyl shikimate-3 phosphate synthase (EPSP inhibition)
Resistance risk: Moderate
The content provided here is for information purposes only and is taken from the Biosecurity Act 2015 and its subordinate legislation, and the Regional Strategic Weed Management Plans (published by each Local Land Services region in NSW). It describes the state and regional priorities for weeds in New South Wales, Australia.
|All of NSW||General Biosecurity Duty
All pest plants are regulated with a general biosecurity duty to prevent, eliminate or minimise any biosecurity risk they may pose. Any person who deals with any plant, who knows (or ought to know) of any biosecurity risk, has a duty to ensure the risk is prevented, eliminated or minimised, so far as is reasonably practicable.
Regional Recommended Measure* (for Regional Priority - Asset Protection)
Land managers should mitigate the risk of the plant being introduced to their land. Land managers should mitigate spread of the plant from their land. A person should not buy, sell, move, carry or release the plant into the environment. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value.
|*To see the Regional Strategic Weeds Management Plans containing demonstrated outcomes that fulfil the general biosecurity duty for this weed click here|